At least 200 passengers have been convicted of felonies under the Patriot Act, often for behavior involving raised voices and profanity. Some experts say airlines are misusing the law.

OKLAHOMA CITY AND LOS ANGELES — Tamera Jo Freeman was on a Frontier Airlines flight to Denver in 2007 when her two children began to quarrel over the window shade and then spilled a Bloody Mary into her lap.

She spanked each of them on the thigh with three swats. It was a small incident, but one that in the heightened anxiety after the Sept. 11 terrorist attacks would eventually have enormous ramifications for Freeman and her children.

A flight attendant confronted Freeman, who responded by hurling a few profanities and throwing what remained of a can of tomato juice on the floor.

The incident aboard the Frontier flight ultimately led to Freeman's arrest and conviction for a federal felony defined as an act of terrorism under the Patriot Act, the controversial federal law enacted after the 2001 attacks in New York and Washington.

"I had no idea I was breaking the law," said Freeman, 40, who spent three months in jail before pleading guilty.

Freeman is one of at least 200 people on flights who have been convicted under the amended law. In most of the cases, there was no evidence that the passengers had attempted to hijack the airplane or physically attack any of the flight crew. Many have simply involved raised voices, foul language and drunken behavior.

Some security experts say the use of the law by airlines and their employees has run amok, criminalizing incidents that did not start out as a threat to public safety, much less an act of terrorism.

In one case, a couple was arrested after an argument with a flight attendant, who claimed the couple was engaged in "overt sexual activity" -- an FBI affidavit said the two were "embracing, kissing and acting in a manner that made other passengers uncomfortable."

"We have gone completely berserk on this issue," said Charles Slepian, a New York security consultant. "These are not threats to national security or threats to aircraft, but we use that as an excuse."

Justice Department spokesman Dean Boyd defended the prosecutions, saying that they have helped improve airline security. He added that the department has only pursued prosecution "when the facts and circumstances of a particular case warrant such action."

Indeed, the law has given airlines new flexibility to clamp down on unruly behavior. But the intent of the Patriot Act provisions was to put terrorists in violation of the law before they could execute an actual takeover, said Nathan Sales, a law professor at George Mason University who helped write the Patriot Act when he served in the Justice Department.

But Sales acknowledged that in the fervor to protect the skies, the practical application of the law has strayed.

"A woman spanking her child is not as great a threat to aviation as members of Al Qaeda with box cutters. That much is clear," he said.

For decades, airline personnel and law enforcement have had wide latitude in prosecuting unruly passengers, not only for assaults or threats but also for any behavior, including arguing, that disrupts a flight or "lessens the ability" of crew members to perform their jobs.

In practice, however, airlines have largely maintained order under Federal Aviation Administration rules, in which hundreds of unruly passengers are simply slapped with an infraction and fine each year.

According to FAA guidelines issued in 2007, "interference or intimidation of a crew member by itself is not chargeable under the [criminal] statute unless it rises to the level of physical assault, threatened physical assault or an act posing an imminent threat to the safety of the aircraft or other individuals on the aircraft."

Sept. 11, however, changed everything. Within two months of the attacks, Congress passed the Patriot Act, a sweeping attempt to improve the nation's defenses against international terrorism. It included broad new powers for law enforcement in such areas as electronic surveillance, money laundering and search warrants.

Included were two key provisions on airline security. The first defined disruptive behavior as a terrorist act, reflecting the seismic shift in airline security.

The second broadened the existing criminal law so that any attempt or conspiracy to interfere with a flight crew became a felony -- a change that allowed flight personnel to act against suspicious passengers even if they hadn't begun an actual assault.

The law gave flight personnel enormous latitude in determining what precisely posed a potential threat or disruption, and judging by some cases, there is no clear standard.

Last summer, a Boston man who took off his clothes and attempted to open an emergency exit during a flight to Los Angeles was not charged with a crime, even though the plane was forced to make an unscheduled landing in Oklahoma City.

Such was not the case with Carl Persing and Dawn Sewell, a Lakewood couple who never left their seats during the 2006 incident aboard a Southwest flight to Raleigh, N.C., that led to their arrests and four days in jail.